diff --git a/src/gui/painting/qicc.cpp b/src/gui/painting/qicc.cpp
index d21bf6b4d93..ba30660fc17 100644
--- a/src/gui/painting/qicc.cpp
+++ b/src/gui/painting/qicc.cpp
@@ -437,6 +437,8 @@ bool parseXyzData(const QByteArray &data, const TagEntry &tagEntry, QColorVector
 
 bool parseTRC(const QByteArray &data, const TagEntry &tagEntry, QColorTrc &gamma)
 {
+    if (tagEntry.size < 12)
+        return false;
     const GenericTagData trcData = qFromUnaligned<GenericTagData>(data.constData()
                                                                   + tagEntry.offset);
     if (trcData.type == quint32(Tag::curv)) {
@@ -564,6 +566,8 @@ bool parseDesc(const QByteArray &data, const TagEntry &tagEntry, QString &descNa
 
     // Either 'desc' (ICCv2) or 'mluc' (ICCv4)
     if (tag.type == quint32(Tag::desc)) {
+        if (tagEntry.size < sizeof(DescTagData))
+            return false;
         Q_STATIC_ASSERT(sizeof(DescTagData) == 12);
         const DescTagData desc = qFromUnaligned<DescTagData>(data.constData() + tagEntry.offset);
         const quint32 len = desc.asciiDescriptionLength;
@@ -643,7 +647,7 @@ bool fromIccProfile(const QByteArray &data, QColorSpace *colorSpace)
             qCWarning(lcIcc) << "fromIccProfile: failed tag offset sanity 2";
             return false;
         }
-        if (tagTable.size < 12) {
+        if (tagTable.size < 8) {
             qCWarning(lcIcc) << "fromIccProfile: failed minimal tag size sanity";
             return false;
         }